Potential Involvement of the South American Lungfish Intelectin-2 in Innate-Associated Immune Modulation

• Published in: International journal of molecular sciences Vol. 25; no. 9; p. 4798
• Main Authors: Bernardes, Gabriela Patrícia Martins de Almeida, Serra, Gustavo Marques, Silva, Lucas da Silva E, Martins, Maíra Pompeu, Perez, Louise Neiva, Molfetta, Fábio Alberto de, Santos, Agenor Valadares, Schneider, Maria Paula Cruz
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 01-05-2024
• Subjects: Amino Acid Sequence; Amino acids; Analysis; Animals; Bacteria; Binding sites; carbohydrate-binding protein; Carbohydrates; Comparative analysis; Fibrin; Fish Proteins - chemistry; Fish Proteins - genetics; Fish Proteins - immunology; Fish Proteins - metabolism; Fishes; Fishes - genetics; Fishes - immunology; GPI-Linked Proteins - chemistry; GPI-Linked Proteins - genetics; GPI-Linked Proteins - immunology; GPI-Linked Proteins - metabolism; Immunity, Innate; innate immunity; lectin; Lectins; Lectins - chemistry; Lectins - genetics; Lectins - immunology; Lectins - metabolism; Ligands; molecular docking; Molecular Docking Simulation; molecular modeling; Monosaccharides; Pathogens; Proteins; RNA; Signal transduction; Skin; Sugars; carbohydrate-binding protein; molecular docking; innate immunity; molecular modeling; lectin
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms25094798

Intelectins belong to a family of lectins with specific and transitory carbohydrate interaction capabilities. These interactions are related to the activity of agglutinating pathogens, as intelectins play a significant role in immunity. Despite the prominent immune defense function of intelectins, limited information about its structural characteristics and carbohydrate interaction properties is available. This study investigated an intelectin transcript identified in RNA-seq data obtained from the South American lungfish (
), namely LpITLN2-B. The structural analyses predicted LpITLN2-B to be a homo-trimeric globular protein with the fibrinogen-like functional domain (FReD), exhibiting a molecular mass of 57 kDa. The quaternary structure is subdivided into three monomers, A, B, and C, and each domain comprises 11 β-sheets: an anti-parallel β-sheet, a β-hairpin, and a disordered β-sheet structure. Molecular docking demonstrates a significant interaction with disaccharides rather than monosaccharides. The preferential interaction with disaccharides highlights the potential interaction with pathogen molecules, such as LPS and Poly(I:C). The hemagglutination assay inhibited lectins activity, especially maltose and sucrose, highlighting lectin activity in
samples. Overall, our results show the potential relevance of LpITLN2-B in
immune defense against pathogens.